Lancaster Bomber

Until the beginning of 1942, when the first Lancaster came off the production line, Wallis had no way of delivering his proposed weapon to the heartland of Germany's industry in the Ruhr Valley.

Britain simply did not posses a bomber that was capable of carrying a 10 ton bomb. After some development on the bomb, Wallis managed to reduce the weight of the bomb to 7,500 pounds which was well within the lifting capability of the new Avro Lancaster.

In 1936, the Air ministry issued a specification for a new type of medium bomber. Chadwick produced the Avro Manchester. This twin engined plane was essentially a sound design, but had one major handicap, the radically new Rolls Royce Vulture engines. These were essentially two engines in one. Chadwick always doubted whether Rolls Royce could devote enough time to the development of the Vulture engine with the approaching war putting major demands on the tried and tested Merlin engine which had to be given priority.

Avro Manchester

Chadwick's fears were justified when the Manchester went into squadron service in November 1940 at RAF Waddington fitted with Vulture engines which were prone to mechanical problems and fires. To solve the problem, Chadwick decided to either replace the Vultures with units of similar power or to fit four less powerful but reliable engines. Even before the Manchester went into service, Chadwick was busy redesigning the plane to house four engines. This would be the Manchester Mk III.

In anticipation of the greater range and load that Bomber command would require as the RAF took the war to the German heartland, Chadwick modified the Manchester to house four Merlin engines. Apart from the engine changes, the Manchester design was so good it did not take much work to come up with the new machine renamed as the Lancaster. In essence the Lancaster was a modified Manchester with four Merlin engines. It flew for the first time in January 1941.

The Key to the Lancaster's success was in the initial design of the Manchester. In the original specification, the Air Ministry had asked that the new bomber be able to carry torpedoes as well as bombs. To accommodate this, Chadwick designed into the Manchester (and later the Lancaster) a huge bomb bay capable of holding an 8,000 pound load. It was therefore able to accommodate new weapons such as Upkeep and later Tallboy while other four engined heavies such as the Stirling and Halifax were limited by their small sectional bomb bays which restricted them to smaller conventional bombs.

Lancaster Bomb Bay

What made the Lancaster stand out even more was its performance while carrying large bomb loads. It was able to increase its payload without compromising its flying performance. This gave the young pilots a huge advantage in the difficult combat flying conditions - especially when it came to accurately delivering Upkeep to the targets.